Joint structure

ABSTRACT

The invention provides a joint structure for use in making articles of furniture suitable for assembly in the home. The joint structure consists of a first element having an axial opening and a transverse opening, a second element for engagement in the transverse opening, and a third element engageable in the axial opening for locking the second element in the transverse opening. The second element includes a notch extending transversely of the second element for engagement by the third element to prevent separation of the second element from the first element.

United States Patent 1191 5/1956 French 287120.924

1111 3,747,965 Wing July 24, 1973 JOINT STRUCTURE 2,861,815 11/1958 Willinger 237/54 A 49,633 8/1865 King 211/182 UX [761' Invent "1"? 2 1,051,427 1/1913 McCluskey 287120.92 L

Ch1pp1wa, Ontario, Canada 22 i June 22, 1971 Primary Examiner-Jordan Franklin Assistant Examiner-Wayne L. Shedd [21] App!" 155594 Attamey-Rogers et a1.

52 us. Cl. 287/54 c, 52/665, 108/111, ABSTRACT 211/177, 21 1l182,'287/20.924, 287/189.36 The invention provides ajoint structure for use in mak- R, 312/257 A ing articles of furniture suitable for assembly in the [51] int. Cl. F1611 7/00 home. The joint structure consists of a first element [58] Field 01 Search 287/189.36 R, 20.92 D, having an axial opening and a transverse opening, a

' 287/2092 Y, 20.924, 54 A, 54 C, 53.5, 56; second element for engagement in the transverse open- 211/177, 178, 182, 183, 148; 182/178; ing, and a third element engageable in the axial opening 108/101, 111,157; 52/665, 667, 495; for locking the second element in the transverse open- I 312/257 A ing. The second element includes a notch extending V transversely of the second element for engagement by [56] References Cited the third element to prevent separation of the second UNITED STATES PATENTS element from the first element. 2,747,236.

3 Claims, 8 Drawing Figures 1 JOINT STRUCTURE This invention relates to a joint structure for use in building articles of furniture, display stands and the like, and more particularly-to a joint structure connecting structural elements.

There is a growing demand for furniture which can be readily assembled by the purchaser in his home. Such furniture has the advantage that it tends to be cheaper to make than conventional furniture because the labour involved in assembly is provided by the pur, chaser rather than the manufacturer. Also, furniture of this type is readily stored in boxes to limit damage to the furniture and also to limit storage space. The boxes are relatively easy to handle and because of the compact arrangement the shipping costs are reduced compared with conventional finished furniture which beinclusion in different articles of furniture.

' In one of its aspects, the present invention provides a joint structure for use in making articles of furniture suitable for assembly in the home. The'joint structure consists of a first element having an atrial opening and a transverse opening, a second element for, engagement in the transverse opening, and.athirdelemcntcngageable in the axial opening for locking the second element in the transverse opening. The second element includes a notch.extendingtransversely of the second element for engagement by the thirdelemsnt to prevent separation of the second elementfrom the first element.

Joint structures are also desirable in many frameworks including those used for displaying goods in stores. Frameworks are available for assembly from a variety of parts so that goods can be placed on the frameworks for display. When the displays are to be changed, the frameworks are disassembled and built in a different form to display other goods. However, pres.- ent frameworks include parts made from elements welded together. These parts tend to be unwieldy and do not afford great flexibility of design in preparing new frameworks. It is desirable that the frameworks be readily dismantled, be attractive when assembled, and require a minimum of labour in assembly and disassembly. Also, it is preferable to have frameworks which can be assembled and disassembled without the use, of tools.

In another of its aspects, the invention provides a joint structure for use in frameworks of the type used in shop displays for connecting elements of the frame.- work, the joint being such that the elements are readily disassembled and reassembled in a different form. The structure is such that the elements can be, of different materials and each element can be coloured or treated independently of the other elements.

These and other aspects of the invention will be better understood with reference to the drawings, wherein:

' FIG. 1 is an cxploded'perspec-tive view of a joint structure according to the invention;

FIG. 2 is a sectional view of a joint structure similar to that shown in FIG. 1;

FIG. 3 is a perspective view of a framework incorporating joint structures similar to those shown in FIG. 1 and FIG. .2;

FIG. 4 is a perspective view of another embodiment of a joint structure;

FIG. 5 is a sectional view on lines 5-5 of FIG. 4;

FIG. 6 is an exploded perspective view of a further embodiment of a joint structure;

FIG. 7 is a perspective view of a panel for use with the joint structures in making a display framework and the like; and

FIG. 8 is a perspective view of an element suitable for use in the joint structures.

Reference is first made to FIG. 1 which illustrates the general arrangement of a basic form of the joint structure. A first element 10 is tubular about a longitudinal axis and defines a radial slot 12 extending longitudinally and adapted to receive a second element 14 snugly. Element 14 defines first and second notches l6, 18 extending transversely of the element 14. When the element 14 is engaged in the slot 12, the notches 16, 18 appear inside the element 10 for engagement by respective third elements 20, 20. Element 20 will be described as typical of both elements and parts of element 20 similar to those described with reference to element 20 will be given primed numerals.

Thirdelement 20 is tubular and has an outer diameter for sliding engagement inside first element 10. Preferably, the element 20 is a light push fit inside the element 1,0, to ensure alignment of the element 20 about the longitudinal axisof the element 10. A recess 22 is formed in an-end of element 20 and has a width substantially equal to the thickness of the second element 14 so that the end of the element 20 passes beyond the adjacent side of the element 14. The recess ensures that sufficient of the element 20 is engaged in the element 10 for proper location of the element 20 thereby perrnitting the element 10 to be relatively small for a given penetration of element 20 within element 10. On assembly, the wall of element 20 of the bottom of the recess 22 engages in notch 16 thereby locking element 14 in element 10. Similarly, the element 20 is engaged in notch 18 to further secure the element 14 in the element 10.

The width of the notches 16, 18 is preferably chosen so that elements 20, 20 engage frictionally in the notches with sufficient force to retain the elements 20, 20' within the element 10. However, this is a matterof choice depending upon the structure being constructed and also whether or not it will subsequently be disassembled into its basic components. An alternative look ing method would be to deform elements 20, 20' adjacent respective notches 22, 22' so that the end extremities of the element adjacent the notches project slightly outwards radially. These extremities would then engage the inner wall of element 10 and frictionally lock the elements 20, 20inside the element 10.

The basic joint" structure shown in FIG. 1- can be modified to connect a plurality of second elements 14. As seen in FIG. 2, second elements l4, l4 engage in respective slots 12, 12' in first element 10. Each of the third elements 20, 20' include diametrically opposed pairs of notches 22, 22 for engagement with the second elements 14,, 14'.

The structure shown in FIG. 2 also illustrates the use of the joint structure for coupling cylindrical uprights 24, 24 to the second elements l4, 14. The uprights 24, 24' preferably have a cross-section similar to that of the first element so that on casual inspection the uprights and first element 10 present a continuous cylindrical appearance through the intersection with the second elements 14, 14. It will be evident that the third elements 24, 24' can be made to be a friction fit in either the first element or an associated one of the uprights 24, 24'.

As will be described with reference to FIG. 6, the third elements 20, can be extended for engagement with subsequent joint structures to eliminate uprights 24, 24. In this case the junction between the second elements 14, 14 and third elements 20, 20' will be emphasized by the appearance of first element 10.

Reference is now made to FIG. 3 which shows a simple framework 26 built according to the invention and consisting of four uprights 28 spaced apart by lower rails 30 and upper rails 32. The rails 30 and 32 meet the uprights 28 at respective joint structures similar to those described with reference to FIG. 1 and FIG. 2. However, the joint structures are arranged so that adjacent rails engage the joint structure at right angles, each of the ends of the rails being formed similarly to the end of second element 14 (FIG. 1). In this framework a single third element 20 is used in each of the lower joint structures whereas in each of the upper joint structures two of the elements 20 are used so that further uprights 28 can be attached by engagement with the projecting third elements.

The framework 26 is typical of an infinite variety of structures which can be made using the joint structures of the present invention. In FIG. 2, the elements 14, 14' are in alignment whereas elements or rails 32 meet at right angles in FIG. 3. It will be evident that the rails can meet the first elements at any desired angle about the longitudinal axis of the first element consistent with the requirements of the framework being constructed. Many other variations are possible, some of which will be described with reference to subsequent figures.

Reference is now made to FIGS. 4 and 5 which show ajoint structure used in the assembly of a table or similar structure. As seen in FIG. 4, an upright first element or leg 34 is coupled to respective second elements or rails 36, 36' by a cap or third element 38. As better seen in FIG. 5, the rails 36, 36' engage in respective slots 40, (one of which is shown) arranged to extend radially through the leg 34 such that the rails 36, 36 are at right angles. The rails have respective notches 42, 42' for engagement by respective tongue portions defined by the wall of a tubular portion 44 of the cap 38. The tongue portions are arranged at the bottom of respective recesses 46, 46 which are enlarged at their leading ends for better engagement on respective rails 36, 36. Because the rails 36, 36' are locked from one side only by the cap 38, it is preferable to define grooves 48, 48 in the sides of respective rails 36, 36' such that the grooves are extensions of respective notches 42, 42'. The recesses 46, 46 are of a width for engagement about the rails 36, 36' in the grooves. As a result, any force tending to separate the rails from the leg 34 will be distributed over a relatively large part of the tubular portion 44 of the cap thereby limiting angular movement of the rails relative to the leg 34.

The cap 38 includes a circular plate 50 attached to an upper end of the portion 44 by welding or any other suitable means and defines a central opening 5.2 through which a screw 54 is engaged in a table top 56.

The structure described with reference to FIGS. 4 and 5 can be duplicated to provide four such structures in making a table having four legs. Alternatively, the angle between rails 36, 36 can be changed so that the table can have any desired number of legs. For instance, a table having six legs would require that the angle between adjacent rails 36, 36' be 120. Similarly, a table having three legs would require this angle to be 60.

Reference is now made to FIG. 6 which illustrates a joint structure incoporating modifications of the previously described structures. In this instance the joint structure includes a first element 56 having a generally triangular cross-section defining three longitudinally extending faces defining respective longitudinal slots 58, 58', and 58". Each of the slots is adapted to receive one of three second elements 60 (one of which is shown), each second element having first and second notches 62, 64 for engagement with respective third elements 66, 68. The element 66 is tubular and defines at one end three recesses 70, 70 and 70" for engagement with second elements 60 in the fashion previously described with reference to FIGS. 1 and 2. The element 66 is a close sliding fit in an opening 72 extending longitudinally through element 56 and meeting the slots 58, 58 and 58". Element 66 differs from element 20 (FIG. 2) in that the element 20 is intended to locate upright 24 such that upright 24 blends into element 10 whereas element 66 is intended to extend upwardly for engagement in a further first element of a framework structure. The upper end of element 66 which is not shown would correspond in shape to the lower end and have recesses 70 positioned as desired for engagement in a further joint structure. Once engaged the element 66 cannot rotate relative to element 56 which increases the rigidity of a framework incorporating elements such as 66.

Although element 66 will be satisfactory in some circumstances, in other it will be desirable to provide a third element which acts simply as location for an upright or other member in a fashion described with reference to FIG. 2. In this event a third member similar to third member 20 (FIG. 2) with suitable changes in the positions of recesses 22, 22' could be used. However, a modified form of third element is shown in FIG. 6 and this element is preferable wherever difficulty is encountered in engaging members such as uprights 24, (FIG. 2) over elements 20.

Element 68 has an end for engagement inside element 56 which end corresponds to the previously described end of element 66. Element 68 is formed of a solid material and is tapered at the outer end and bifurcated by a slot 74. The slot extends axially beyond a tapered portion 76 and the diameter of the element 68 is such that it is a close fit in an upright 78 of a framework. Once the slot 74 is formed, a wedge is forced into the slot to spread the bifurcated end sufficiently to require force to be applied to engage upright 78 over element 68. The slot provides space for deflection so that the inherent resiliency of the material of the element 68 acts to retain the element in the upright 78.

Although third element 68 is more expensive to make than previously described third elements, element 68 is preferable because the tapered portion 76 facilitates engagement of upright 78 over the element 68.

FIG. 6 also illustrates a panel 80 suitable for engagement between pairs of vertically-spaced second ele- 'upper and lower faces 86, 88. Each of the channels 82,

84 is adapted to engage an element 60 to locate the panel 80 in the framework. For instance, the framework shown in FIG. 3 could have a panel at one side supported between corresponding rails 30, 32 with the rails engaged inrespective channels 82, 84 of the panel 80.

In some instances where the material of the panel is sufficiently' rigid,-a panel structure can be used for engagement directly in joint structures. Such a panel is shown in FIG. 7 and is generally rectangular having parallel pairs of projections 90, 92 each of which is essentially a third element in a joint structure. Each projection 90, 92 can be engaged in a suitable first element such as element 56 (FIG. 6) and then locked in place by a third element such as element 66 (also FIG. 6). For the sake of appearance, it is probable that an upright will be incorporated between projections 9'1) to matchthe appearance of the rest of the structure. However, this upright is not structurally required because of the rigidity of panel 89. In the event that an upright is used, suitable third elements will be incorporated for engagement in first elements 56 and in upright 78 used between the third elements. It should be noted that each of the projections 90,92 incorporates a notch on its outward facing side for engagement by a third element 66. It would be impossible to assemble a third element into engagement with inwardly facing sides of the projections and for this reason no notch is included on these sides.

It will be evident from the foregoing description that wherever a joint structure is used having third elements incorporating recesses such as recesses 70, 7t) and 70" (FIG. 6), different third elements must be provided for different combinations of second elements meeting the first element. Although the number of third elements required can be reduced by for instance having four recesses at one end for use wherever right angles are used, between second elements, the number of third elements can be further reduced by the use of an element such as that shown in FIG. 8. In this embodiment of the third element one end of the element has three recesses for use where second elements meet at 120 and at the other end of the element four recesses for use where second elements meet at 90. In any particular construction of a joint structure the end of element shown in FIG. 8 corresponding to the particular situation is inserted in a first element to lock second elements in place.

In the foregoing description the third elements incorporated recesses. For instance element (FIG. 1) had a recess 22 for engagement about second element 14. While this arrangement is desirable so that the maximum length of third element is engaged in the first element for improved rigidity, a plain piece of tubing having suitable dimensions can be used in place of third element 20. For instance, if element 20 were inverted and the other end of the element inserted, provided that the notch 16 is suitably dimensioned, the third element 20 could engage in the notch and lock the second element in place as previously described. While such an arrangement would be suitable in many instances, it would not be suitable where the third element must be restrained from rotating. This would be the situation in which an element such as element 66 (FIG. 6) has an upper extremity including recesses for engagement in a further first element so that once assembled the joint structures at either end of the third element 66 will be locked in position to limit relative movement between these joint structures. In general, any suitable form of third element can be used provided that the element is proportioned for engagement in a suitable notch in the second element. Also, although tubular and cylindrical elements have been described, it'will be evident that elements having any suitable cross-section can be used provided the other elements are suitably shaped for combination according to the invention.

Among the advantages of the present invention is that the elements can be formed of different materials or treated differently. For instance, the aluminum could be used and anodized for second elements with chromium-plated steel for the primary elements and uprights. Similarly, some or all of the elements can be of plastics or plastic coated material. Various colour combinations can be used as required. This advantage is of particular importance in display structures which up to the present have had limited flexibility due to the welded joint structures;

What I claim is:

l. A framework of the type used in display stands, furniture and the like, the framework including a plurality of uprights and rails interconnected at joint structures, each said joint structure comprising a first element defining a vertically extending opening and a slot having a cross-section similar to that of the rails and extending horizontally into the opening, one of said rails being engaged in the slot; a tubular further element being engaged in the opening, said further element being a sliding fit in the opening and said .one of the rails defining a notch within said opening and extending transversely of the rail, the width of the notch being substantially equal to the wall thickness of the tubular further element and said further element including a portion engaged in the notch, the tubular further element projecting vertically beyond the first element to define a portion on which one of said uprights is engaged whereby said one of the rails is coupled to the said upright with the respective longitudinal axes of the upright and rail being in a common vertical plane.

2. A framework as claimed in claim I in which the first element is tubular and has internal and external diameters, and in which the further element is tubular and has an outer diameter substantially equal to the internal diameter of the first element, the wall thickness of the further element being substantially equal to the width of said notch.

3. A framework as claimed in claim 1 in which the slot is one of a plurality of slots in the first element and in which there is one rail engaged in each one of the slots, said further element being engaged in the notches in the respective rails to lock the rails in the first element. 

1. A framework of the type used in display stands, furniture and the like, the framework including a plurality of uprights and rails interconnected at joint structures, each said joint structure comprising a first element defining a vertically extending opening and a slot having a cross-section similar to that of the rails and extending horizontally into the opening, one of said rails being engaged in the slot; a tubular further element being engaged in the opening, said further element being a sliding fit in the opening and said one of the rails defining a notch within said opening and extending transversely of the rail, the width of the notch being substantially equal to the wall thickness of the tubular further element and said further element including a portion engaged in the notch, the tubular further element projecting vertically beyond the first element to define a portion on which one of said uprights is engaged whereby said one of the rails is coupled to the said upright with the respective longitudinal axes of the upright and rail being in a common vertical plane.
 2. A framework as claimed in claim 1 in which the first element is tubular and has internal and external diameters, and in which the further element is tubular and has an outer diameter substantially equal to the internal diameter of the first element, the wall thickness of the further element being substantially equal to the width of said notch.
 3. A framework as claimed in claim 1 in which the slot is one of a plurality of slots in the first element and in which there is one rail engaged in each one of the slots, said further element being engaged in the notches in the respective rails to lock the rails in the first element. 